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Gantt & critical path templates

All Four Dependencies — FS, SS, FF and SF, With Lead and Lag

Every precedence relationship in one plan, which Mermaid cannot express at all: finish-to-start, start-to-start, finish-to-finish and start-to-finish, each with a lag or a lead. `+10cd` is ten ELAPSED days — concrete does not stop curing on a Saturday — and the engine converts that to working days from wherever the predecessor actually lands. Reports clean.

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Template previewGantt & critical path
Ground floor slab — Gantt chart with critical path10 tasks; from 2026-05-04 to 2026-06-10, 28 working days; 8 on the critical path; every check ran and found nothing.Ground floor slabMo 4 May 2026 → We 10 Jun 2026 · 28 working days · 38 calendar dayscritical path: dig → base → pour → cure → strip → steel → survey → slabshorten first: dig (up to 8d) · cure (up to 6d) · steel (up to 6d)May 2026Jun 2026Mo4Tu5We6Th7Fr8Sa9Su10Mo11Tu12We13Th14Fr15Sa16Su17Mo18Tu19We20Th21Fr22Sa23Su24Mo25Tu26We27Th28Fr29Sa30Su31Mo1Tu2We3Th4Fr5Sa6Su7Mo8Tu9We10GroundworksFollowing onSS+2dFFSF▲ Excavate8d · shorten → 8dShoring5d · float 21d▲ Blinding and formwork4d · shorten → 4d▲ Pour slab2d · shorten → 2d▲ Cure6d · shorten → 6d▲ Strip formwork2d · shorten → 2d▲ Steel erection6d · shorten → 6d▲ As-built survey3d · shorten → not…Night watch handover4d · float 6d▲ Slab complete2026-06-10critical — zero floatnear-criticalhas floattotal floatmilestonenon-working daybaselineEvery check ran, and none of them found anything.·Mo 4 May 2026 to We 10 Jun 2026 — 28 working days across 38 calendar days, on a Mo–Fr week·one critical path, through 8 tasks — shortening any one of them shortens the project, up to the point another path becomes binding·to finish sooner, shorten `dig` by up to 8 working days (the whole task); `cure` by up to 6 working days (the whole task); `steel` by up to 6 working days (the whole task). Anything beyond those figuresmoves nothing — the gain from taking δ days off a task is min(δ, the figure above), and it is zero for every critical task not listed here.

Make it your own.

title "Ground floor slab"
start 2026-05-04
calendar mon-fri

section "Groundworks"
  task dig   "Excavate" 8d
  task shore "Shoring" 5d after ss:dig +2d
  task base  "Blinding and formwork" 4d after dig
  task pour  "Pour slab" 2d after base
  task cure  "Cure" 10cd after pour
  task strip "Strip formwork" 2d after cure

section "Following on"
  task steel "Steel erection" 6d after strip
  task survey "As-built survey" 3d after ff:steel
  task night "Night watch handover" 4d after sf:steel
  milestone slab "Slab complete" after survey